A rotary brush device of a conventional upright vacuum cleaner has been formed with a rotary brush which is housed in a floor nozzle and is driven by an electric blower motor for sucking dust. The motor is built in the main body of vacuum cleaner, and the motor through a belt or gears drives the rotary brush, or a dedicated motor is provided outside the rotary brush somewhere in a floor nozzle to drive the brush.
The conventional construction discussed above requires a considerably large space for the mechanism transmitting the rotating force. This has been a blocking factor for making an apparatus smaller in size and lighter in weight. This also has caused inconvenience of handling the apparatus.